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作 者:杜纪山[1]
机构地区:[1]西北林学院
出 处:《浙江林业科技》1990年第2期20-23,35,共5页Journal of Zhejiang Forestry Science and Technology
摘 要:用陕西省主要林区收集的油松标准地、标准木分析了带、去皮正形数系列f_(0.nh)(0.n=0.0,0.02,0.04,0.06,0.08,0.1,0.15,0.2,0.25,0.3,0.4,0.5)之间的变化规律n对林分得到:当0.n=0.15时,f_(0.nh)(带皮)≈f_(0.n)(去皮);当0.n<0.15时,f_(0.nh)(带皮)<f_(0.nh)(去皮);当0.15<0.n≤0.5时,f_(0.nh)(带皮)>f_(0.nh)(去皮)。单株木也是如此。应用关系式f_(0.15h)(带皮)≈f_(0.15h)(去皮),可根据0.15h处的带、去皮直径,得到树皮率系数,为准确估计单株木树干树皮率、去皮材积、树皮材积提供了一个新途径。经刺槐、红桦、白桦、山杨验证,也获得同样的结果。The change law of a series of normal form factors f_(0.nh)(0. n = 0. 0,0. 02,0. 04,0.06, 0.08, 0. 1, 0. 15, 0.2, 0. 25, 0.3, 0. 4, 0. 5) between over-bark and under-bark was analysedby sample plots and sample trees for Pinus tabulaeformis in main forests of Shaanxi. Theresult showed for stand: 0. n = 0. 15, f_(0.nh(0 .b))≈ f_(0.nh(u .b)); 0. n<0.15, f_(0.nh(0 .b))<f_(0.nh(u .b));0. 15<0.n<0.5, f_(0.nh(0.b))>f_(0.nh(u.b)); so did for single tree. It is a new way that coefficient ofbark volume is obtained by applying f_(0.1sh(0.b))≈f_(0.1sh(u.b)) and diameter of o. b and u. b in0.15 relative height for accurate estimation of bark volume rate, u.b volume and bark volumeto single trees. The similar result has been gte to Robinia pseudoacacia, Betula utilis var.sinensis, Betula platyphylla and Populus davidiana.
分 类 号:S758.1[农业科学—森林经理学]
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